<HTML><HEAD><TITLE>*(+Number1, +Number2, -Result)</TITLE>
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<H1>*(+Number1, +Number2, -Result)</H1>
Evaluates the product Number1 * Number2 and unifies the resulting value
with Result.


<DL>
<DT><EM>Number1</EM></DT>
<DD>A number.
</DD>
<DT><EM>Number2</EM></DT>
<DD>A number.
</DD>
<DT><EM>Result</EM></DT>
<DD>A variable or a number.
</DD>
</DL>
<H2>Description</H2>
   This predicate is used by the ECLiPSe compiler to expand evaluable
   arithmetic expressions.  So the call to *(Number1, Number2, Result) is
   equivalent to
<PRE>
    Result is Number1 * Number2
</PRE>
    which should be preferred for portability.
<P>
   The result is of type breal if any of the arguments is a breal,
   else float if any of the arguments is a float, else rational if any
   of the arguments is a rational.  Only when both arguments are
   integers is the result an integer.

<P>
   In coroutining mode, if Number1 or Number2 are uninstantiated, the call
   to */3 is delayed until these variables are instantiated.

<P>

<H3>Modes and Determinism</H3><UL>
<LI>*(+, +, -) is det
</UL>
<H3>Exceptions</H3>
<DL>
<DT><EM>(4) instantiation fault </EM>
<DD>Number1 or Number2 is not instantiated (non-coroutining mode    only).
<DT><EM>(24) number expected </EM>
<DD>Number1 or Number2 is not of a numeric type.
</DL>
<H2>Examples</H2>
<PRE>
Success:
      *(5, 2, 10).
      *(5, -2.0, -10.0).
Fail:
      *(1, 2, 3).
      *(5, 2, 10.0).
      *(5, 2.0, 10).
      *(1, 2, 3.0).
      *(5, 2, r).
Error:
      *(A, 2, 6).             (Error 4).
      *(4 + 2, 2, 12).        (Error 24).



</PRE>
<H2>See Also</H2>
<A HREF="../../kernel/arithmetic/is-2.html">is / 2</A>
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